Abstract
Although iron and copper are co-ordinately regulated in living cells, the homeostatic effects of each of these metals on the other remain unknown. Here, we show the function of AfMac1, a transcriptional activator of the copper and iron regulons of Aspergillus fumigatus, on the interaction between iron and copper. In addition to the copper-specific AfMac1-binding motif 5'-TGTGCTCA-3' found in the promoter region of ctrC, the iron-specific AfMac1-binding motif 5'-AT(C/G)NN(A/T)T(A/C)-3' was identified in the iron regulon but not in the copper regulon by ChIP sequence analysis. Furthermore, mutation of the AfMac1-binding motif of sit1 eliminated AfMac1-mediated sit1 up-regulation. Interestingly, the regulation of gene expression in the iron regulon by AfMac1 was not affected by copper and vice versa AfMac1 localized to the nucleus under iron- or copper-depleted conditions, and AfMac1 was mostly detected in the cytoplasm under iron- or copper-replete conditions. Taken together, these results suggest that A. fumigatus independently regulates iron and copper homeostasis in a manner that involves AfMac1 and mutual interactions.
Keywords:
A. fumigatus; AfMac1; Saccharomyces cerevisiae; copper; iron.
© 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Aspergillus fumigatus / genetics
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Aspergillus fumigatus / metabolism*
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Copper / metabolism*
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Fungal Proteins / genetics
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Fungal Proteins / metabolism*
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Gene Expression Regulation, Fungal*
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Response Elements*
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Transcription Factors / genetics
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Transcription Factors / metabolism*
Substances
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Fungal Proteins
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Transcription Factors
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Copper